My suggestion is to stop upgrading bios from 1.2.2. Dell introduced show stopper bugs and throttling beyond this bios version. You'll have more problems than the older bios. Might as well wait until Dell reaches bios ver 3 or 10, they might be able to fix it lol
Don't think it is a BIOS issue, more of a driver/conflict issue. Try using some of the tips in this post, some people have said it resolves their problem. But one thing is certain, Dell should have addressed this problem a long time ago instead of burying their head in the sand !!!!
I ran the online diagnostic from the Dell web site which found a USB driver that required upgrading. Did the upgrade and the keyboard skipping problem seems to be solved. For now.
Dell XPS 15 - 9570 - V key has to be pressed twice to type it - and it's clearly software. I hate all the experience with XPS from sleep issues, to keys now randomly deciding to not be typed .. QA should be improved before having updates made guys - it's ridiculous. It was working perfectly before an update.